M4 CS ~ Track Upgrades

[Scott_L]

Had my M4 CS for about 15 months now. Just ticked over 12k miles, all on the road, relatively easy miles.

Getting back into trackdays and rather than sell the CS planned a few modest upgrades, with the intention of sharpening it up a bit.

Here's the planned upgrades:

Bilstein B16 Damptronic
Millway camber plates
Pagid RSC 1 brake pads (for the OE carbon ceramic discs)
Goodridge braided brake lines
Pirelli Trofeo R's (f 265/35/19 r 295/30/20)
M Performance v1 steering wheel (to replace the stupidly phat standard wheel)

Might end up remapping it to release a bit more power and improve the delivery but for now it's standard.

Bilsteins and Millway camber plates went on today. My trusted engineer did the job without any issues.

Rear ride height unchanged, front ride height -20mm...so a bit more rake. Front camber is -1.6 degrees. Suspension is standard other than above so no other geometry changes from standard.

Immediately a very noticeable improvement in chassis composure and control. The car feels significantly more precise and neutral. Excellent stability, no nervousness. No increase in NVH.

Car feels very good on the road. Confidence inspiring. Next track outing in a couple of weeks.

Want to keep it a civilised road car so will resist the temptation to start stripping out weight, fitting a cage/harnesses etc...

Another other worthwhile mods to consider? Likewise any input on setup?

[dvq]

My only suggestions would be a set of M2C steel rotors and track pads — and not track on those ccbs — they’re too expensive to be track consumables.

[F80Speed77]

If you have camber plates definitely increase the front angle to at least -3.0deg.

[NYG]

Two things:

Trofeo-R are not worth the money for track days. That's a ridiculously expensive tire. I've never put them on the CS and they're really good but unless you're competing you're going to be wasting so much money on a tire that won't last more than 2 days while being a huge liability on the road, especially if you're in rainy England.

Switch to iron rotors, metallic pads and a big brake kit. Pads and rotors are consumables and like the Trofeo-R, you're going to be spending way too much money even if they do last longer than iron rotors/metallic pads.

Based on my experience with the M4CS:

-1.6 front camber will limit your cornering grip and destroy your tires even faster. That's about what you get stock (-1.4ish on mine). It's a dual duty car and I don't have the time to do track specific camber setups so I don't take it into the -3.0s (If it's a track car then definitely start considering -3.0s and toe out on the front). I used the recommendations of people on here for -2.5 being a great set it and forget it front camber and it's a really good recommendation. I went to -2.6 just to get a better temperature gradient for Lime Rock Park but it's a very minimal change and -2.5 worked beautifully for me at the tracks I frequent most (NJMP/Watkins Glen/LRP). If you do track days at Silverstone, I'd probably tell you to go -2.6-2.7. I've never been there so my opinion is based on watching F1 and sim racing (take it with a grain of salt if you must)

0 Front Toe is, in my opinion, one of the things you'll feel the impact of instantly. Toe-out is better for a track duty car but I wouldn't do it for street. The car wants to oversteer... a lot but way easier to control and tame than other RWD cars I've been in.

I haven't had any complaints with -1.8 on my rear and about 1/16th total toe-in. The toe change in the rear will be obvious in corners.

I have the M-Perf wheel with the shift lights, if that's the same one, it's WAY thicker than the stock wheel. I actually loved the stock wheel thickness.

Brake ducting is a really good idea on this car but you're kind of limited because the front end of is a wall of radiators.

Nitto NT01 is a tire I personally love for track days, mainly because of value. My rear tires were still in great shape and gripping well after more than 10 track days. Fronts went out quick because I ran that stock camber for the first 2-3 days. It is definitely not the grippiest tire out there but for non-competition it makes a lot of sense. Can't compare to Trofeo Rs but I can tell you I'm 2 seconds faster at Lime Rock Park with NT01s than I am with Cup 2s.

[Scott_L]

Originally Posted by NYG

Two things:

Trofeo-R are not worth the money for track days. That's a ridiculously expensive tire. I've never put them on the CS and they're really good but unless you're competing you're going to be wasting so much money on a tire that won't last more than 2 days while being a huge liability on the road, especially if you're in rainy England.

Switch to iron rotors, metallic pads and a big brake kit. Pads and rotors are consumables and like the Trofeo-R, you're going to be spending way too much money even if they do last longer than iron rotors/metallic pads.

Based on my experience with the M4CS:

-1.6 front camber will limit your cornering grip and destroy your tires even faster. That's about what you get stock (-1.4ish on mine). It's a dual duty car and I don't have the time to do track specific camber setups so I don't take it into the -3.0s (If it's a track car then definitely start considering -3.0s and toe out on the front). I used the recommendations of people on here for -2.5 being a great set it and forget it front camber and it's a really good recommendation. I went to -2.6 just to get a better temperature gradient for Lime Rock Park but it's a very minimal change and -2.5 worked beautifully for me at the tracks I frequent most (NJMP/Watkins Glen/LRP). If you do track days at Silverstone, I'd probably tell you to go -2.6-2.7. I've never been there so my opinion is based on watching F1 and sim racing (take it with a grain of salt if you must)

0 Front Toe is, in my opinion, one of the things you'll feel the impact of instantly. Toe-out is better for a track duty car but I wouldn't do it for street. The car wants to oversteer... a lot but way easier to control and tame than other RWD cars I've been in.

I haven't had any complaints with -1.8 on my rear and about 1/16th total toe-in. The toe change in the rear will be obvious in corners.

I have the M-Perf wheel with the shift lights, if that's the same one, it's WAY thicker than the stock wheel. I actually loved the stock wheel thickness.

Brake ducting is a really good idea on this car but you're kind of limited because the front end of is a wall of radiators.

Nitto NT01 is a tire I personally love for track days, mainly because of value. My rear tires were still in great shape and gripping well after more than 10 track days. Fronts went out quick because I ran that stock camber for the first 2-3 days. It is definitely not the grippiest tire out there but for non-competition it makes a lot of sense. Can't compare to Trofeo Rs but I can tell you I'm 2 seconds faster at Lime Rock Park with NT01s than I am with Cup 2s.

Thanks for this. Much appreciated.

My next track outing in the M4 is at Donington.

Will take your advice on camber and toe settings...and maybe even corner weight it!

Forgive my ignorance but is -1.8º possible with the standard suspension?

[NYG]

It was with mine but I had the MP HAS installed on it which may have helped? It's maxed out though.

[MyFragileHalogen]

Originally Posted by NYG

Two things:

Nitto NT01 is a tire I personally love for track days, mainly because of value. My rear tires were still in great shape and gripping well after more than 10 track days. Fronts went out quick because I ran that stock camber for the first 2-3 days. It is definitely not the grippiest tire out there but for non-competition it makes a lot of sense. Can't compare to Trofeo Rs but I can tell you I'm 2 seconds faster at Lime Rock Park with NT01s than I am with Cup 2s.

[ABenLauda]

Originally Posted by Scott_L

Forgive my ignorance but is -1.8º possible with the standard suspension?

My ///M technician could go only upto -1.4 with stock suspension on mine.

[fanatic1]

Maxed out rear camber at -2.1°. The limiter is rear toe as stock adjustability is limited. To maintain optimal rear toe, you’re either stuck at low camber or investing in toe arms.

[F80Speed77]

I picked up the Fall line camber bolt shim kit and it looks like it made a big change to rear camber with the max camber shims in place. I still need to get the car aligned but we have the stock arms maxed out and it looks like I'm still getting a little bit of toe out at the rear. Might have to finally bite the bullet and get the aftermarket arms.

[CanAutM3]

Originally Posted by Scott_L

Thanks for this. Much appreciated.

My next track outing in the M4 is at Donington.

Will take your advice on camber and toe settings...and maybe even corner weight it!

Forgive my ignorance but is -1.8º possible with the standard suspension?

-1.8 is the factory nominal specs for the rear. I actually dial it down a bit to -1.6 to optimize rear tire grip and wear, but that could vary depending on the track and speed.

[CanAutM3]

Originally Posted by abenney

My ///M technician could go only upto -1.4 with stock suspension on mine.

That’s surprising given -1.8deg is the nominal BMW factory spec for the rear...

[fanatic1]

Originally Posted by F80Speed77

I picked up the Fall line camber bolt shim kit and it looks like it made a big change to rear camber with the max camber shims in place. I still need to get the car aligned but we have the stock arms maxed out and it looks like I'm still getting a little bit of toe out at the rear. Might have to finally bite the bullet and get the aftermarket arms.

Did the same with Max camber shims and got -2.1°, curious what your max is?

[F80Speed77]

Waiting on a few more odds and ends to come in before I get a full alignment but I'll keep you posted when I do. It was at around -1.8 before I added them and I was getting more shoulder wear than I liked.

[fanatic1]

Originally Posted by F80Speed77

Waiting on a few more odds and ends to come in before I get a full alignment but I'll keep you posted when I do. It was at around -1.8 before I added them and I was getting more shoulder wear than I liked.

Pretty easy DIY install on toe links, 2 fasteners

Note image has oem camber Eccentric adjustment in this image

[RSXDC5]

You need the Girodisc F/R 2-piece steel racing rotors. I talked to Girodisc a couple days ago and their rears will be out in a month once they validate fitment on their design with a local. If u want to use the oem carbons for track work, u can, they work well, but stop using them when u hit the half wear point if u want to continue to run them on the street.

[ashmostro]

Hey all, I know this is an old thread but the topic is spot-on to my questions. Hopefully some of you are still subscribed.

I am in the process of purchasing an M4cs, to replace my M2cs, for track duty. I run advanced HPDE with a goal of competing in TT's in the coming year(s).

I have a set of Essex/AP BBK that I will be pulling off my F87 and will fit perfectly onto the F82. That said, the car I am buying comes with the CCBs which I will obviously not use on the track but I could drop in some Paragon or Girodisc rotors and sell off the AP kit. My concern is pad knockback, which was the main reason I bought the AP kit for the F87. I will also be transplanting the full SPL Parts spherical bearing suspension (I purchased literally every one), which exacerbates pad knockback due to the total lack of bump compliance (putting all of the impact load into the wheel bearings).

So yeah, will I get knockback on the stock calipers with floating aftermarket rotors, or will it be minimal? I'm thinking it's still going to be considerable but I have no data to test the hypothesis.

Thanks!